The Japan Coast Guard plans to use three new large patrol boats to beef up maritime security in waters near the Senkaku Islands in the East China Sea.
Maritime activity by Chinese government ships in the region remains high.
Twelve patrol ships are now deployed at Ishigaki Island in Okinawa Prefecture to monitor the area near the Senkaku Islands.
Sources say the three surveillance ships will be deployed at Kagoshima Port, close to Okinawa, by the end of March 2021.
The over-6,000-ton vessels, now under construction, are each capable of carrying two helicopters.
They would be less affected by bad weather, and could function as operational headquarters.
Japan controls the Senkaku Islands. The Japanese government maintains the islands are an inherent part of Japan's territory. China and Taiwan claim them.
Chinese government ships have entered Japan's territorial waters around the Senkaku Islands a number of times since 2012. The Japanese government acquired ownership of some of the islands from a private owner that year.